Please note, this is a STATIC archive of website www.w3resource.com from 19 Jul 2022, cach3.com does not collect or store any user information, there is no "phishing" involved.
w3resource

Pandas: Convert year and day of year into a single datetime column of a dataframe

Pandas Time Series: Exercise-12 with Solution

Write a Pandas program to convert year and day of year into a single datetime column of a dataframe.

Sample Solution:

Python Code :

import pandas as pd
data = {\
"year": [2002, 2003, 2015, 2018],
"day_of_the_year": [250, 365, 1, 140]
}
df = pd.DataFrame(data)
print("Original DataFrame:")
print(df)
df["combined"] = df["year"]*1000 + df["day_of_the_year"]
df["date"] = pd.to_datetime(df["combined"], format = "%Y%j")
print("\nNew DataFrame:")
print(df)

Sample Output:

Original DataFrame:
   year  day_of_the_year
0  2002              250
1  2003              365
2  2015                1
3  2018              140

New DataFrame:
   year  day_of_the_year  combined       date
0  2002              250   2002250 2002-09-07
1  2003              365   2003365 2003-12-31
2  2015                1   2015001 2015-01-01
3  2018              140   2018140 2018-05-20

Python Code Editor:


Have another way to solve this solution? Contribute your code (and comments) through Disqus.

Previous: Write a Pandas program to create a sequence of durations increasing by an hour.
Next: Write a Pandas program to create a series of Timestamps from a DataFrame of integer or string columns. Also create a series of Timestamps using specified columns.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.



Python: Tips of the Day

Find current directory and file's directory:

To get the full path to the directory a Python file is contained in, write this in that file:

import os 
dir_path = os.path.dirname(os.path.realpath(__file__))

(Note that the incantation above won't work if you've already used os.chdir() to change your current working directory, since the value of the __file__ constant is relative to the current working directory and is not changed by an os.chdir() call.)

To get the current working directory use

import os
cwd = os.getcwd()

Documentation references for the modules, constants and functions used above:

  • The os and os.path modules.
  • The __file__ constant
  • os.path.realpath(path) (returns "the canonical path of the specified filename, eliminating any symbolic links encountered in the path")
  • os.path.dirname(path) (returns "the directory name of pathname path")
  • os.getcwd() (returns "a string representing the current working directory")
  • os.chdir(path) ("change the current working directory to path")

Ref: https://bit.ly/3fy0R6m